Spectral and luminescent properties of trivalent samarium ions in KLu(WO4)2 crystals

The crystals of Sm3+-doped KLu(WO4)2 with large dimensions up to 40 mm × 33 mm × 13 mm have been grown by the top-seeded solution growth (TSSG) method. The spectral and luminescent properties have been investigated. Based on the Judd–Ofelt theory, the following spectral parameters have been obtained: the phenomenological intensity parameters Ωt, Ω2 = 15.728 × 10−20 cm2, Ω4 = 4.223 × 10−20 cm2 and Ω6 = 2.839 × 10−20 cm2, radiative transition probabilities AJ,J′AJ,J′ and oscillator strengths PJ,J′PJ,J′. The radiative lifetime of levels 4G5/2 is 748 μs. However, the measured emission lifetime is τem = 569 μs. The quantum efficiency is very low because of the excited state absorption. In addition, the values of integrated emission cross-sections are also calculated.